<template>
    <div id="app">
        <h3>案例：折叠面板</h3>
        <div class="box">
            <div class="title">
                <h4>芙蓉楼送辛渐</h4>
                <span @click="isShow = !isShow" class="btn">
                    {{ isShow ? '收起' : '展开' }}
                </span>
            </div>
            <div v-show="isShow" class="container">
                <p>寒雨连江夜入吴,</p>
                <p>平明送客楚山孤。</p>
                <p>洛阳亲友如相问，</p>
                <p>一片冰心在玉壶。</p>
            </div>
        </div>
    </div>
</template>

<script>
export default {
    data() {
        return {
            isShow: true
        }
    }
}
</script>

<style lang="less">
body {
    background-color: #ccc;

    #app {
        width: 400px;
        height: 320px;
        margin: 20px auto;
        background-color: #fff;
        border: 4px solid blueviolet;
        border-radius: 1em;
        box-shadow: 3px 3px 3px rgba(0, 0, 0, 0.5);
        padding: 1em 2em 2em;

        h3 {
            text-align: center;
        }

        .box {
            box-shadow: 0 1px 4px 0 rgba(0, 0, 0, 0.5);
            border-radius: 4px;
            border: 1px solid #ebeef5;
            background-color: #fff;
            overflow: hidden;
            color: #303133;
            transition: .3s;
        }

        .title {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 10px 20px;
        }

        .title h4 {
            line-height: 2;
            margin: 0;
        }

        .container {
            padding: 0 20px;
            border-top: 1px solid #ccc;
        }

        .btn {
            /* 鼠标改成手的形状 */
            cursor: pointer;
        }
    }
}
</style>